Elbow Orthosis

ABSTRACT

An orthosis for stretching tissue around a joint of a patient between first and second relatively pivotable body portions. The orthosis includes a first arm member affixable to the first body portion and including a first extension member extending therefrom. A second arm member affixable to the second body portion is also included and has a second extension member having an arcuate shape extending therefrom. A third arm member including a third extension member having an arcuate shape extending therefrom is interposed between the first and second arm members. The third arm member is operatively connected to the first and second arm members, such that the first and third arm members travel along an arcuate path defined by the second extension member when the third arm member is moved from a first position to a second position relative to the second arm member. Furthermore, the first arm member can slide along the third extension member as the third arm member is moved from the first position to the second position relative to the second arm member.

CROSS-REFERENCE TO RELATED APPLICATION

The present application claims priority to U.S. Provisional PatentApplication No. 60/783,895 filed Mar. 20, 2006, entitle ELBOW ORTHOSIS,the contents of which are herein incorporated by references in itsentirety.

FIELD OF THE INVENTION

The present invention relates to an adjustable orthosis for stretchingtissue in the human body. In particular, the present invention relatesto an adjustable orthosis which can be used for stretching tissue suchas ligaments, tendons or muscles around a joint during flexion orextension of the joint.

BACKGROUND OF THE INVENTION

In a joint, the range of motion depends upon the anatomy of that jointand on the particular genetics of each individual. Typically, jointsmove in two directions, flexion and extension. Flexion is to bend thejoint and extension is to straighten the joint; however, in theorthopedic convention some joints only flex. For example, the ankle hasdorsiflexion and plantarflexion. Other joints not only flex and extend,they rotate. For example, the elbow joint has supination and pronation,which is rotation of the hand about the longitudinal axis of the forearmplacing the palm up or the palm down.

When a joint is injured either by trauma or by surgery, scar tissue canform, often resulting in flexion or extension contractures. Suchconditions can limit the range of motion of the joint, limiting flexion(in the case of an extension contracture) or extension (in the case of aflexion contracture) of the injured joint. It is often possible tocorrect this condition by use of a range-of-motion (ROM) orthosis.

ROM orthoses are devices commonly used during physical rehabilitativetherapy to increase the range-of-motion over which the patient can flexor extend the joint. Commercially available ROM orthoses are typicallyattached on opposite members of the joint and apply a torque to rotatethe joint in opposition to the contraction. The force is graduallyincreased to increase the working range or angle of joint motion.Exemplary orthoses include U.S. Pat. No. 6,599,263, entitled “ShoulderOrthosis;” U.S. Pat. No. 6,113,562, entitled “Shoulder Orthosis;” U.S.Pat. No. 5,848,979, entitled “Orthosis;” U.S. Pat. No. 5,685,830,entitled “Adjustable Orthosis Having One-Piece Connector Section ForFlexing;” U.S. Pat. No. 5,611,764, entitled “Method of Increasing Rangeof Motion;” U.S. Pat. No. 5,503,619, entitled “Orthosis for BendingWrists;” U.S. Pat. No. 5,456,268, entitled “Adjustable Orthosis;” U.S.Pat. No. 5,453,075, entitled “Orthosis with Distraction through Range ofMotion;” U.S. Pat. No. 5,395,303, entitled “Orthosis with Distractionthrough Range of Motion;” U.S. Pat. No. 5,365,947, entitled “AdjustableOrthosis;” U.S. Pat. No. 5,285,773 entitled “Orthosis with Distractionthrough Range of Motion;” U.S. Pat. No. 5,213,095, entitled “Orthosiswith Joint Distraction;” and U.S. Pat. No. 5,167,612, entitled“Adjustable Orthosis,” all to Bonutti and herein are expresslyincorporated by reference in their entirety.

SUMMARY OF THE INVENTION

The present invention provides an orthosis for stretching tissue arounda joint of a patient between first and second relatively pivotable bodyportions. The joint and the first and second body portions define on oneside of the joint an inner sector which decreases in angle as the jointis flexed and define on the opposite side of the joint an outer sectorwhich decreases in angle as the joint is extended.

The orthosis includes a first arm member affixable to the first bodyportion. The first arm member has a first extension member extendingtherefrom. A second arm member affixable to the second body portion isalso included. The second arm member has a second extension memberhaving an arcuate shape extending therefrom. A third arm memberincluding a third extension member, having an arcuate shape extendingtherefrom, is interposed between the first and second arm members. Thesecond and third arm members are operatively connected, such that thethird arm member travels along an arcuate path defined by the secondextension member when the third arm member is moved from a firstposition to a second position relative to the second arm member. Thefirst arm member is slidingly connected to the third extension member,such that the first arm member slides along an arcuate path defined bythe third extension member when the third arm member is moved from thefirst position to the second position relative to the second arm member.

The orthosis further includes a drive assembly for selectively movingthe third arm member relative to the second extension member. The driveassembly is mounted onto the third arm member, engaging the secondextension member. The drive assembly can be manually or automaticallyactuated to selectively move the third arm member relative to the secondextension member.

BRIEF DESCRIPTION OF THE DRAWINGS

A more complete understanding of the present invention, and theattendant advantages and features thereof, will be more readilyunderstood by reference to the following detailed description whenconsidered in conjunction with the accompanying drawings wherein:

FIG. 1 is a schematic diagram of the orthosis of the present inventionin a flexed position;

FIG. 2 is a schematic diagram of the orthosis of the present inventionin an extended position;

FIG. 3 is a second schematic diagram of the orthosis of the presentinvention in a flexed position;

FIG. 4 shows an adjustable first extension member of the orthosis of thepresent invention;

FIG. 5 shows the adjustable first extension member of FIG. 4 in a secondposition;

FIG. 6 shows a segmented first extension member of the presentinvention;

FIG. 7 shows an arcuate first extension member of the present invention;

FIG. 8 shows an orthosis of the present invention;

FIG. 9 shows a non-circular arcuate shaped second extension member ofthe present invention;

FIG. 10 shows an alternative arcuate shaped second extension member ofthe present invention;

FIG. 11 shows a linear shaped second extension member of the presentinvention;

FIG. 12 shows an exemplary drive assembly of the present invention;

FIG. 13 depicts a first side view of another orthosis of the presentinvention for flexing and extending a joint in a patient;

FIG. 14 depicts an opposite side view of the orthosis of FIG. 13;

FIG. 15 depicts a first arm member of the orthosis of FIG. 13;

FIG. 16 depicts a second arm member of the orthosis of FIG. 13;

FIG. 17 depicts a third arm member of the orthosis of FIG. 13;

FIG. 18 depicts the drive assembly of the orthosis of FIG. 13;

FIG. 19 depicts the connectivity of the first, second, and third armmembers of the orthosis of FIG. 13;

FIG. 20 depicts the orthosis of FIG. 13 in a middle flexed position; and

FIG. 21 depicts the orthosis of FIG. 13 in a fully flexed position.

DETAILED DESCRIPTION OF THE INVENTION

The present invention relates to an orthosis for moving a joint betweenfirst and second relatively pivotable body portions. The joint and thefirst and second body portions define on one side (the flexor side) ofthe joint an inner sector which decreases in angle as the joint isflexed (bent) and on the opposite side (the extensor side) of the jointan outer sector which decreases in angle as the joint is extended(straightened). The orthosis of the present invention is affixable toeither the flexor or extensor side of the joint for treatment of flexionor extension contractures.

Referring now to the drawing figures in which like reference designatorsrefer to like elements, there is shown in FIG. 1, a schematic of theorthosis 10 of the present invention. The orthosis 10 includes a firstarm member 12 attachable to the first body portion and a second armmember 14 attachable to the second body portion, wherein a joint axis ofrotation 16 is interposed between and offset from the first and secondarm members 12 and 14. The first and second arm members 12 and 14 areoperatively connected to each other offset from the joint axis 16.

The first arm member 12 of the orthosis 10 includes a First extensionmember 18, which extends at angle α from the first arm member 12. Thesecond arm member 14 of the orthosis 10 includes a second extensionmember 20 extending therefrom and having an arcuate shape. The first andsecond extension members 18 and 20 are operatively connected at point“P,” such that in operation the second extension member 20 travels alongan arcuate path about and substantially through point “P.” The arcuateshape of the second extension member 20 results in the second bodyportion rotating about the joint axis 16, when the second arm member 14is moved from a first position to a second position relative to thefirst arm member 12. The angle α between the first extension member 18and the first arm member 12 and the radius of curvature of the secondextension member 20 are a function of the joint to be treated and thedegree of flexion or extension contractures.

The orthosis further includes a drive assembly 22 at point “P.” Thedrive assembly connects the first and second extension members 18 and 20for applying force to the first and second arm members 12 and 14 topivot the first and second body portions relative to each other aboutthe joint.

The orthosis 10 of the present invention is shown having an angle α suchthat the operative connection, at point “P.” of the first and secondextensions 18 and 20 is located in a plane “A” passing through the jointaxis 16, wherein plane “A” is substantially orthogonal to a longitudinalaxis of the first arm member 12. This position of point “P” provides anangle β₁ between the second arm member 14 and the joint axis 16, whereinβ₁ is the maximum angle of flexion. As shown in FIG. 2, the secondextension member includes a stop 24. The stop 24 acts to limit the angleof maximum extension γ between the second arm member 14 and the jointaxis 16. An increase in the length of the stop 24 will decrease theangle of maximum extension γ. A decrease in the length of the stop 24will increase the angle of maximum extension γ.

Referring to FIG. 3, the maximum flexion angle can be increased byincreasing the angle α. An increase in the angle α will move the point“P” to a location “in front of” the plane “A.” This position of point“P” provides an angle β₂ between the second arm member 14 and the jointaxis 16 in maximum flexion, wherein β₂ is greater than β₁. The greaterthe angle α, the greater the angle of maximum flexion.

Alternatively, (not shown) a decrease in the angle α will move the point“P” to a location “behind” the plane “A.” This position of point “P”provides an angle β₃ between the second arm member 14 and the joint axis16 in maximum flexion, wherein β₃ is less than β₁. The smaller the angleα, the smaller the angle β of maximum flexion.

Referring to FIG. 4, the first extension member 18 is selectively,pivotally connected at location 26 to the first arm member 12. Thepivotal connection 26 of the first extension member 18 permits the angleα between the first extension member 18 and the first arm member 12 tobe selectively increased and decreased, increasing and decreasing therange of motion. In a first position 28, the first extension member 18is positioned at an angle α₁, wherein the operative connection, at point“P,” of the first and second extension members 18 and 20 is located in aplane “A” passing through the joint axis 16, wherein plane “A” issubstantially orthogonal to a longitudinal axis of the first arm member12. The first position 28 of point “P” provides a maximum angle offlexion of β₁. The second extension member stop 24 acts to limit theangle of maximum extension γ₁ between the second arm member 14 and thejoint axis 16.

Referring to FIG. 5, in a second position 30 the angle α is increased toan angle α₂, positioning the point “P” to a location “in front of” theplane “A.” The second position 30 of point “P” provides a maximum angleof flexion of β₂, wherein β₂ is greater than β₁. The second extensionmember stop 24 acts to limit the angle of maximum extension γ₂ betweenthe second arm member 14 and the joint axis, wherein γ₂ is less the γ₁.

The selective pivotal connection 26 of the first extension member 18 tothe first arm member 12 can have a plurality of selectable positions.The angle α between the first arm member 12 and the first extension 18can be selectively increased to move the point “P”, on, “in front of” or“behind” the plane “A.” It is also envisioned that a positioned can beselected to increase the angle α between the first arm member 12 and thefirst extension 18 sufficiently to move the point “P” “in front of”plane “A” and “above” the longitudinal axis of the first arm member 12,maximizing the maximum angle of flexion β.

The orthosis 10 of the present invention can be connected to the flexorside of the first and second body portions of the joint, which resultsin a decrease in angle as the joint is flexed (bent) and an increase inangle and the joint is extended (straightened). Alternatively, orthosis10 of the present invention can be connected to the extensor side of thejoint, which results in a decrease in angle as the joint is extendedstraightened and an increase in angle as the joint is flexed (bent).

The previous description of the first arm member 12 depicts a firstextension 18 having a substantially linear shape, extending at an angleα from the first arm member 12. However, it is within the scope of thepresent invention that the first extension member 18 can be any shapeextending from the first arm member 12 which positions the point “P” inthe desired relationship to the plane “A.” Referring to FIG. 6, asegmented first extension member is shown, including a first extensionmember segment 18 a and a second extension member segment 18 b. Thefirst and second extension member segments 18 a and 18 b extend from thefirst arm member 12, positioning the point “P” at an angle α from thefirst arm member 12. Referring to FIG. 7, an arcuate first extensionmember 18 c is shown. The arcuate extension member 18 c extends from thefirst arm member 12, positioning the point “P” at an angle α from thefirst arm member 12.

Referring to FIG. 8, the orthosis 10 of the present invention includes afirst arm member 12 attachable to the first body portion and a secondarm member 14 attachable to the second body portion, wherein the jointaxis 16 is interposed between and offset from the first and second armmembers 12 and 14. The first and second arm members 12 and 14 areconnected with each other offset from the joint axis 16.

The first arm member 12 of the orthosis 10 includes a first extensionmember 18, which extends at angle α from the first arm member 12. Thesecond arm member 14 of the orthosis 10 includes a second extensionmember 20, having an arcuate shape. The first and second extensionmembers 18 and 20 are operatively connected a point “P,” such that inoperation the second extension member 20 travels along an arcuate pathabout and substantially through point “P.” The arcuate shape of thesecond extension member 20 results in the second body portion rotatingabout the joint axis 16, when the second arm member 14 is moved from afirst position to a second position relative to the first arm member 12.The angle α between the first extension member 18 and the first armmember 12 and the radius of curvature of the second extension member 20are a function of the joint to be treated and the degree of flexion orextension contractures.

A first cuff 32 is attached to the first arm member 12, wherein thefirst cuff 32 is positionable about the first body portion. The firstcuff 32 is attached to the first body portion by cuff straps. The firstcuff 32 secures the first body portion to the first arm member 12. Asecond cuff 34 is attached to the second arm member 14, wherein thesecond cuff 34 is positionable about the second body portion. The secondcuff 34 is attached to the second body portion by cuff straps. Thesecond cuff 34 secures the second body portion to the second arm member14. (The term “cuff” as used herein means any suitable structure fortransmitting the force of the orthosis 10 to the limb portion itengages.)

In an exemplary use, the orthosis 10 is operated to extend a joint inthe following manner. The first cuff 32 is fastened about the first bodyportion tightly enough that the first arm member 12 may apply torque tothe first body portion without having the first cuff 32 slide along thefirst body portion. Similarly, the second cuff 34 is fastened securelyaround the second body portion so that the second arm member 14 mayapply torque to the second body portion without the second cuff 34sliding along the second body portion. The orthosis 10 is attached tothe first and second body portions in a first position. The second armmember 14 is rotated from the first position to a second position,relative to the first arm member 12, rotating the second body portionabout the joint axis 16 stretching the joint. As the second arm member14 is rotated to the second position, the second extension member 20travels along an arcuate path about and substantially through point “P.”The orthosis 10 is maintained in the second position for a predeterminedtreatment time providing a constant stretch to the joint. The orthosis10 may alternatively be configured to impart a constant force or load onthe joint or may utilize the techniques of Static Progressive Stretch asdescribed in co-pending application Ser. No. 11/203,516, entitled “Rangeof Motion System and Method”, and filed on Aug. 12, 2005, the entiretyof which is incorporated by reference.

Additionally, the second extension member 12 can be made of asubstantially rigid but flexible material, such that while the secondextension member 12 is in the second position, the second extensionmember 12 acts like a spring, providing dynamic stretch to theconnective tissue of the joint.

After the expiration of the treatment time, the second arm member 14 ismoved back to the first position, relieving the joint. Optionally, thesecond arm member 14 can be rotated to a third position, increasing thestretch on the joint. The second arm member 14 can be rotated atdiscrete time intervals to incrementally increase the stretch of thejoint through the treatment cycle. After completion of the treatmentcycle, the second arm member is returned to the first position forremoval of the orthosis 10.

The first and second arm members 12 and 14 are rigid members made of,for example, aluminum. stainless steel, polymeric, or compositematerials. The arms are rigid so as to be able to transmit the necessaryforces. It should be understood that any material of sufficient rigiditycan be used.

In an embodiment, the components of the orthosis 10 of the presentinvention are made by injection molding. Generally for injectionmolding, tool and die metal molds of the orthosis 10 components areprepared. Hot, melted plastic material is injected into the molds. Theplastic is allowed to cool, forming components. The components areremoved from the molds and assembled. The cuff portions 32 or 34 can beindividual molded and attached to the arm members 12 or 14.Alternatively, the cuff portions can be molded as an integrated part ofthe arm members 12 or 14.

In use, the orthosis 10 can be connected to the flexor side of the firstand second body portions of the joint, which results in a decrease inangle as the joint is flexed (bent) and an increase in angle as thejoint is extended (straightened). Alternatively, orthosis 10 of thepresent invention can be connected to the extensor side of the joint,which results in a decrease in angle as the joint is extendedstraightened and an increase in angle as the joint is flexed (bent).

In an embodiment, the orthosis 10 includes a first cuff 32 forattachment to a first body portion, and a second cuff 34 for attachmentto a second body portion. The first body portion is joined to the secondbody portion at a joint, around which is located, as is well known, softtissue. Each of the first and second cuffs 32 and 34 includes loopconnectors for receiving straps extending around the body portions toclamp the cuffs 32 and 34 to the body portions.

The first cuff 32 is mounted for sliding movement on the first armmember 12 and is slidable along the first arm member 12 in a manner asdescribed below. The second cuff 34 is mounted for sliding movement on asecond arm member 14 and is slidable along the second arm member 12 in amanner as described below.

Bending a Joint in Extension:

In operation of the orthosis 10 to extend the joint, the orthosis 10starts at a more flexed position. The first and second cuffs 32 and 34are clamped onto the first and second body portions, respectively, bystraps, tightly enough so that the cuffs 32 and 34 can apply torque tothe body portions to extend the joint. The second arm member 14 isrotated from the first position to a second position, relative to thefirst arm member 12, rotating the second body portion about the jointaxis 16 stretching the joint. As the second arm member 14 is rotated tothe second position the second extension member 20 travels along anarcuate path about and substantially through point “P.” The orthosis 10is maintained in the second position for a predetermined treatment timeproviding a constant stretch to the joint.

As the orthosis 10 is rotated from the first position to the secondposition, extending the joint, the first and second cuffs 32 and 34 movealong the first and second arm members 12 and 14. The first cuff 32moves inwardly along the first arm member 12. Similarly, the second cuff34 moves inwardly along the second arm member 14. Because the cuffs 32and 34 are clamped onto the first and second body portions as describedabove, the outward pivoting movement of the first and second arm members12 and 14 and the cuffs 32 and 34 causes the joint to be extended asdesired. However, this extension of the joint can place strongdistractive forces on the soft tissues around the joint. The slidingmovement of the cuffs 32 and 34, inwardly along the first and second armmembers 12 and 14, helps to limit these distractive forces bycounteracting the outward movement of the first and second arm members12 and 14. The cuffs 32 and 34 slide inwardly along the first and secondarm members 12 and 14 a distance far enough so that the joint is onlyslightly distracted during extension. Thus, the detrimental effects ofstrong distractive forces normally generated in forced extension of ajoint are avoided, being replaced with the beneficial effects of limitedand controlled distraction.

Bending a Joint in Flexion:

In operation of the orthosis 10 to flex the joint, the orthosis 10starts at a more extended position. The first and second cuffs 32 and 34are clamped onto the first and second body portions, respectively, bystraps, tightly enough so that the cuffs 32 and 34 can apply torque tothe body portions to extend the joint. The second arm member 14 isrotated from the first position to a second position, relative to thefirst arm member 12, rotating the second body portion about the jointaxis 16 stretching the joint. As the second arm member 14 is rotated tothe second position the second extension member 20 travels about andsubstantially though point “P,” along an arcuate path. The orthosis 10is maintained in the second position for a predetermined treatment timeproviding a constant stretch to the joint.

As the orthosis 10 is rotated from the first position to the secondposition, flexing the joint the first and second cuffs 32 and 34 movealong the first and second arm members 12 and 14. The first cuff 32moves outwardly along the first arm member 12. Similarly, the secondcuff 34 moves outwardly along the second arm member 14. Because thecuffs 32 and 34 are clamped onto the first and second body portions theinward pivoting movement of the first and second arm members 12 and 14and the cuffs 32 and 34 causes the joint to be flexed as desired.However, this flexion of the joint can place strong compressive forceson the soft tissues around the joint. The sliding movement of the cuffs32 and 34, outwardly along the first and second arm members 12 and 14,helps to limit these compressive forces by counteracting the inwardmovement of the first and second arm members 12 and 14. The cuffs 32 and34 slide outwardly along the first and second arm members 12 and 14 adistance Far enough so that the joint is only slightly compressed duringflexion. Thus, the detrimental effects of strong compressive forcesnormally generated in forced flexion of a joint are avoided, beingreplaced with the beneficial effects of limited and controlledcompression.

Referring to FIG. 9, the second arm member 14 is shown having anon-circular arcuate shaped second extension member 44. The non-circulararcuate shaped second extension member 44 provide an axis of rotationwhich changes as the second arm member 14 is moved from the firstposition to the second portion. As such, as the second arm member 14 ismoved from the first position to the second portion the second bodyportion will exhibit both a rotational motion, about the joint axis 16,and a translational motion, distracting or compressing the joint.

In the previously described embodiments, the arcuate shape of the secondextension member 20 or 44 as shown have concave radius of curvaturerelative to the joint 16. However, referring to FIG. 10, it iscontemplated that the second extension member 20 or 44 can have a convexradius of curvature relative to the joint 16. Similar to the concaveradius of curvature, the convex arcuate shape of the second extensionmember 20 or 44 results in the second body portion rotating about thejoint axis 16, when the second arm member 14 is moved from a firstposition to a second position relative to the first arm member 12.

Referring to FIG. 11, the second arm member 14 of the orthosis 10includes a second extension member 46 extending therefrom and having alinear shape. The first and second extension members 18 and 46 areoperatively connected at point “P,” such that in operation the secondextension member 46 travels along a linear path through point “P.” Thelinear shape of the second extension member 46 results in the secondbody portion being translated with respect to the first body portion.The translational movement of the second arm member 14 results in adistraction or compression of the joint when the second arm member 14 ismoved from a first position to a second position relative to the firstarm member 12.

As discussed further below, the hand pad can be mounted fortranslational and rotational movement on the base member.

Drive Assembly:

Referring to FIG. 12, the drive assembly 22 of the orthosis includes agear system. As previously noted, the components of the orthosis,including the drive assembly 22, can be made by injection molding apolymer. The drive assembly 22 is supported in the first extensionmember 18, including a gear 50 rotatable about point “P.” A shaft 52,attached to the gear 50, extends from first extension member 18. A knob54 is connected to the shaft 52, opposite the gear 50, for manuallyrotating the gear 50. The second extension member 20 includes a seriesof teeth 56 along an inner surface 58. The second extension member 20 isthreaded through the first extension member 18, such that the teeth 56on the second extension member 20 engage the gear 50. The rotation ofthe knob 56 causes the gear 50 to rotate, pushing or pulling the secondextension member 20 through the first extension member 18. The driveassembly 22 includes a locking or breaking mechanism which prevents thegear 50 from rotating absent any applied Force rotation of the knob 56.Such a lock or breaking mechanism can include a compression washer orother known gear locking or breaking mechanisms.

The drive assembly 22 is described as utilizing a gear system. However,it is contemplated that other known drive systems can be used to movethe second extension member 20 through the first extension member 18,for example a friction type drive system. Regardless of the drive systemused, the joint orthosis of the present invention can act as a brace,restricting the relative movement of the first and second body portionsto one degree of freedom (e.g. flexion and extension about the joint).Thus, drive assembly 22 can be configured to allow free motion in onedegree of freedom. This can be achieved in a number of different ways.For example, gear 50 can be positioned such that it does not engageteeth 56.

In an alternative embodiment, the drive assembly 22 of orthosis 10 inaccordance with the present invention can be actuated by a motor insteadof by a manually actuatable member. Likewise, the motor may beconfigured an adapted with gearing that causes the orthosis to cyclethrough a range of motion in a predetermined manner, or alternativelymaybe controlled by a programmable logic controller (PLC).

In an embodiment, an electric motor is mounted to the shalt 52 forrotation of the gear 50. A battery provides electric power to the motor.Alternatively, the motor can be supplied with external power. Amicroprocessor controls the operation of the motor. The microprocessorand motor together can be used to cycle the first and second arm members12 and 14 through extension and flexion; to move the first and secondarm members 12 and 14 in one pivotal direction a certain amount, holdthere while tissue stretches, then move further in that direction; or inany other manner.

In another manner of use, the orthosis can be set to cycle to one end ofthe joint's range of motion and hold there for a predetermined period oftime, then cycle to the other end of the joints range of motion and holdthere. The programming and control of the microprocessor is within theskill of the art as it relates to driving the motor to control the firstand second arm members 12 and 14 to move in known manners. Thisembodiment is ideally suited for continuous passive motion exercise,because the orthosis is portable and because the motor can be programmedwith the desired sequence of movements.

It should be understood that the particular physical arrangement of themotor, the battery, and the microprocessor is not the only possiblearrangement of those elements. The invention contemplates that otherarrangements of these or similarly functional elements are quitesuitable, and thus the invention is intended to cover any sucharrangement. Additionally, another type of power source, other than anelectric motor, can also be used. For example, the use of a hydraulic orpneumatic motor as the drive mechanism is contemplated.

Referring to FIGS. 13 and 14, an orthosis 80 of the present inventionincludes a first arm member 82 attachable to the first body portion anda second arm member 84 attachable to the second body portion, whereinthe joint axis 86 is interposed between and offset from the first andsecond arm members 82 and 84. A third arm member 88 is interposedbetween the first and second arm members 82 and 84, where the first andsecond arm members 82 and 84 are connected to the third arm member 88,offset from the joint axis 86.

The first arm member 82 of the orthosis 80 includes a first extensionmember 90, which extends from the first arm member 82. The second armmember 84 of the orthosis 80 includes a second extension member 92having an arcuate shape. The first and second extension members 90 and92 are operatively connected to the third arm member 88, where thesecond extension member 92 is operably connected to the third arm member88 at a point “P,” such that in operation the third member 88 travelsalong an arcuate path of the second extension member 92. The arcuateshape of the second extension member 92 results in the first bodyportion rotating about the joint axis 86, when the first and third armmembers 82 and 88 are moved from a first position to a second positionrelative to the second arm member 84. The radius of curvature of thesecond extension member 92 is a function of the joint to be treated andthe degree of flexion or extension contractures.

A first cuff 94 is attached to the first arm member 82, wherein thefirst cuff 94 is positionable about the first body portion. The firstcuff 94 is attached to the first body portion by cuff straps. The firstcuff 94 secures the first body portion to the first arm member 82. Asecond cuff 96 is attached to the second arm member 84, wherein thesecond cuff 96 is positionable about the second body portion. The secondcuff 96 is attached to the second body portion by a cuff strap(s) 98.The second cuff 96 secures the second body portion to the second armmember 84. The cuffs 94 and 96 can be provided in a variety of sizes orhave adjustable sizes to fit about the body portions. (The term “cuff”as used herein means any suitable structure for transmitting the forceof the orthosis 80 to the limb portion it engages.).

The first cuff 94 can be slidingly connected to the first arm member 82.Referring to FIG. 15, a sliding bar 100 is affixed to the first cuff 94.where the sliding bar 100 includes channels 102 positioned on oppositesides of the sliding bar 110. The first arm member 82 includes a mainchannel 106 configured to slidingly receive the sliding bar 100. Pins108 are positioned though opposite sides of the main channel 106 of thefirst arm member 82 and into the channels 102 to slidingly secured thesliding bar 100 in the main channel 106. An adjustable member 110 can bethreaded though the first arm member 82, into a channel 102 toadjustably secure the position of the sliding bar 102 in the mainchannel 106. As such, the position of the first cuff 94 can be adjustedwith respected the first arm member 82, the position being secured withthe adjustable member 110. Alternatively, the first cuff 94 can be freeto slide with respect to the first arm member 82, thereby allowing theposition of the first cuff 94 to self adjust during operation of theorthosis 80.

Similar to the first cuff 92, the second cuff 96 can be slidinglyconnected to the second arm member 84.

Referring to FIG. 16, the second extension member 92 has an arcuateshape, where the radius of curvature of the second extension member 92is a function of the joint to be treated and the degree of flexion orextension contractures. The second extension member 92 includes an innersurface 112 have a plurality of teeth 114 thereon. The second extensionmember 92 can include channels 115 disposed on opposite sides thereof.

Referring to FIG. 17, the third arm member 88 includes a third extensionmember 116 has an arcuate shape, where the radius of curvature of thethird extension member 116 is a function of the joint to be treated andthe degree of flexion or extension contractures. The third extensionmember 116 includes channels 118 disposed on opposite sides thereof. Adrive housing 120 is positioned proximal to a guide channel 122.

Referring also to FIGS. 18 and 19, a drive assembly 124 is positioned inthe drive housing 120 of the third arm member 88. The drive assembly 124includes a drive gear 126 and a main gear 128, where the teeth of thedrive gear 126 engage the teeth 130 of the main gear 128. A drive shaft132 is connected to the drive gear 126, extending through the coverplate 134. A knob 133 can be affixed to the drive shaft 132 tofacilitate rotation thereof. A rotation of the drive shaft 132 rotatesthe drive gear 126, which in turn rotates the main gear 128. The maingear 128 is sized such that a portion of the gear teeth 130 protrudesinto the guide channel 122 of the third arm member 88.

The second extension member 92 is positioned in the guide channel 122,such that the gear teeth 132 of the main gear 128 engage the teeth 114on the inner surface 112 of the second extension member 92. A rotationof the dive shaft 132 rotates the drive gear 126, which in turn rotatesthe main gear 128, driving the second extension member 92 through theguide channel 122. The cover plate 134 is positioned over the guidechannel 122, securing the second extension member 92 in the guidechannel 122 and defining a passage through which it travels.

Guide pins 135 can be positioned in the channels 115 of the secondextension member 92, engaging on one side the third arm member 88 and onan opposite side the cover plate 134. The guide pins 135 can be used tosecure the second extension member 92 in the passage and control thetacking of the third arm member 88 along the second extension member 92.

The drive mechanism 22 can further include a locking mechanism. Thelocking mechanism can be used to secure the position of the second armmember 84 with respect to the third arm member 88. The locking mechanismcan prevent the actuation of the drive assembly 124, securing theposition of second and third arm members 84 and 88. Alternatively, thelocking mechanism can secure the second and third arm members 84 and 88,preventing an actuation of the drive mechanism 124 from moving thesecond and third arm members 84 and 88. The locking mechanism can beutilized such that the orthosis 80 can be used as a static splint.

The first arm member 82 can be sliding affixed to the third arm member88. The first extension member 90 is positioned about the thirdextension member 88, where an end portion 136 of the first extensionmember 90 is slidingly connected about the third extension member 118.Pins 140 are positioned through pin holes 142, provided on oppositesides of the end portion 136 of the first extension member 90, into thechannels 118 of the third extension member 88, thereby allowing the endportion 136 of the first extension member 90 to slide along the arcuatepath defined by the channels 118, rotating the first arm member 82 aboutthe joint axis 86. The first arm member 82 can slide freely with respectto the third extension member 116. Alternatively, a push pin 144 can bepositioned through the end portion 136 of the first extension member 92into push pin hole 146 in the channels 118 of the third extension member116. (See also FIG. 14). The push pin 144 prevents relative movement ofthe first arm member 82 with respect to the third arm member 88.

In an exemplary use, the orthosis 80 is operated to extend a joint inthe following manner. The first cuff 94 is fastened about the first bodyportion tightly enough that the first arm member 82 may apply torque tothe first body portion without having the first cuff 94 slide along thefirst body portion. Similarly, the second cuff 96 is fastened securelyaround the second body portion so that the second arm member 84 mayapply torque to the second body portion without the second cuff 96sliding along the second body portion. The orthosis 80 is attached tothe first and second body portions in a first position. The first andsecond arm members 82 and 84 are rotated from the first position to asecond position, relative to the second arm member 84, rotating thefirst body portion about the joint axis 86 stretching the joint. As thefirst and second arm members 82 and 84 are rotated to the secondposition, the third arm member 88 travels along an arcuate path alongthe second extension member 92. The orthosis 80 is maintained in thesecond position for a predetermined treatment time providing a constantstretch to the joint. Additionally, the second extension member 92 canbe made of a substantially rigid but flexible material, such that whilethe first arm member 82 is in the second position the second extensionmember 92 acts like a spring, providing dynamic stretch to theconnective tissue of the joint.

After the expiration of the treatment time, the first arm member 82 ismoved back to the first position, relieving the joint. Optionally, thefirst arm member 82 can be rotated to a third position, increasing thestretch on the joint. The first arm member 82 can be rotated at discretetime intervals to incrementally increase the stretch of the jointthrough the treatment cycle. After completion of the treatment cycle,the first arm member 82 is returned to the first position for removal ofthe orthosis 80.

In another exemplary use, the push pin 144 is removed from the first andthird arm members 82 and 88, such that as the first and third armmembers 82 and 88 are moved from a first position to a second position,with respected to the second arm member 84, the first arm member 82 canslide along the arcuate path of the third extension 116 of the third armmember 88. This can be utilized to increase the range on motion of theorthosis 80. It is contemplated that the orthosis 80 can have a range ofmotion from around 15 degrees to around 145 degrees.

The first, second, and third arm members 82, 84, and 88 are rigidmembers made oft for example, aluminum, stainless steel, polymeric, orcomposite materials. The arms are rigid so as to be able to transmit thenecessary forces. It should be understood that any material ofsufficient rigidity can be used.

In an embodiment, the components of the orthosis 80 of the presentinvention are made by injection molding. Generally for injectionmolding, tool and die metal molds of the orthosis 80 components areprepared. Hot, melted plastic material is injected into the molds. Theplastic is allowed to cool, forming components. The components areremoved from the molds and assembled. The cuff portions 92 or 96 can beindividual molded and attached to the arm members 82 or 84.Alternatively, the cuff portions can be molded as an integrated pant ofthe arm members 82 or 84.

Similarly, the gears 132 and 134 are rigid members made of, for example,aluminum, stainless steel, polymeric, or composite materials. The gears132 and 134 are rigid so as to be able to transmit the necessary forces.

Bending an Elbow Joint Flexion:

In operation of the orthosis 80 to flex an elbow joint, the orthosis 80starts at a more extended position. The first and second cuffs 94 and 96are clamped onto the forearm and bicep portions of the arm,respectively, by straps, tightly enough so that the cuffs 94 and 96 canapply torque to the body portions to flex the joint. The first andsecond arm members 82 and 84 are rotated from the first position to asecond position, relative to the second arm member 84, rotating theforearm about the elbow joint axis 86 stretching the joint. As the firstand second arm members 82 and 84 are rotated to the second position thethird arm member 88 travels along the arcuate path of the secondextension member 92. The orthosis 80 is maintained in the secondposition for a predetermined treatment time providing a constant stretchto the joint.

After the expiration of the treatment time, the first and second armmembers 82 and 884 are moved back to the first position, relieving thejoint. Optionally, the first and second arm members 82 and 84 can berotated to a third position, increasing the stretch on the joint. Thefirst and second arm members 82 and 84 can be rotated at discrete timeintervals to incrementally increase the stretch of the joint through thetreatment cycle. Referring to FIG. 20, the treatment cycle can continueuntil the third arm member 88 traverses the second extension member 82.After completion of the treatment cycle, the first and second armmembers 82 and 84 are returned to the first position for removal of theorthosis 80.

Alternatively, the first arm member 82 can be released to move along thethird arm member 88. Referring to FIG. 21, the first and third armmembers 82 and 88 are rotated from the first position to a secondposition, relative to the second arm member 84, rotating the forearmabout the joint axis 86 stretching the joint. As the third arm member 88is rotated to the second position, the first arm member 82 can travelalong an arcuate path of the third extension member 116, therebyincreasing the range of motion.

Bending an Elbow Joint in Extension:

When an elbow joint is to be bent in extension, the first cuff 94 isconnected with the forearm and the second cuff 96 is connected to thebicep. The first and second cuffs 94 and 96 are clamped onto the forearmand biceps respectively, by straps, tightly enough so that they canapply torque to flex the joint. The first and third arm members 82 and88 are rotated from the first position to a second position, relative tothe second arm member 84, rotating the forearm about the elbow jointaxis 86 stretching the joint. As the first and third arm members 82 and88 are rotated to the second position the third arm member 88 travelsalong the arcuate path of the second extension member 92. The orthosis80 is maintained in the second position for a predetermined treatmenttime providing a constant stretch to the joint.

After the expiration of the treatment time, the first and second armmembers 82 and 84 are moved back to the first position, relieving thejoint. Optionally, the first and second arm members 82 and 84 can berotated to a third position, increasing the stretch on the joint. Thefirst and second arm members 82 and 84 can be rotated at discrete timeintervals to incrementally increase the stretch of the joint through thetreatment cycle. After completion of the treatment cycle, the first andsecond arm members 82 and 84 are returned to the first position forremoval of the orthosis 80.

Alternatively, the first arm member 82 can be released to move along thethird arm member 88. The first and third arm members 82 and 88 arerotated from the first position to a second position, relative to thesecond arm member 84, rotating the second body portion about the jointaxis 86 stretching the joint. As the third arm member 88 is rotated tothe second position, the first arm member 82 can travel along an arcuatepath of the third extension member 116, thereby increasing the range ofmotion.

In the above description, the second and/or third extension members 92and 116 are shown and described as having a substantially circulararcuate shape, positioning the axis of rotation at the joint axis 86.However, it is contemplated that the second and/or third extensionmembers 92 and 116 can have alternative shapes.

The drive assembly 124 is described as utilizing a gear system. However,it is contemplated that other known drive systems can be used to movethe first extension member 90 with respect to the second extensionmember 92 for example a friction type drive system. Regardless of thedrive system used, the joint orthosis of the present invention can actas a brace, restricting the relative movement of the first and secondbody portions to one degree of freedom (e.g. flexion and extension aboutthe joint). Thus, drive assembly 124 can be configured to allow freemotion in one degree of freedom. This can be achieved in a number ofdifferent ways. For example, gear 128 can be positioned such that itdoes not engage teeth 130.

In an alternative embodiment, the drive assembly 124 of orthosis 80 inaccordance with the present invention can be actuated by a motor insteadof by a manually actuatable member, such as the knob 133. Likewise, themotor may be configured and adapted with gearing that causes theorthosis to cycle through a range of motion in a predetermined manner,or alternatively maybe controlled by a programmable logic controller(PLC).

In an embodiment, an electric motor is mounted to the shaft 132 forrotation of the gear 128. A battery provides electric power to themotor. Alternatively, the motor can be supplied with external power. Amicroprocessor controls the operation of the motor. The microprocessorand motor together can be used to cycle the second and third arm members84 and 88 through extension and flexion; to move the first and secondarm members 82 and 84 in one pivotal direction a certain amount, holdthere while tissue stretches, then move further in that direction; or inany other manner.

In another manner of use, the orthosis can be set to cycle to one end ofthe joint's range of motion and hold there for a predetermined period oftime, then cycle to the other end of the joints range of motion and holdthere. The programming and control of the microprocessor is within theskill of the art as it relates to driving the motor to control thesecond and third arm members 84 and 88 to move in known manners. Thisembodiment is ideally suited for continuous passive motion exercise,because the orthosis is portable and because the motor can be programmedwith the desired sequence of movements.

It should be understood that the particular physical arrangement of themotor, the battery, and the microprocessor is not the only possiblearrangement of those elements. The invention contemplates that otherarrangements of these or similarly functional elements are quitesuitable, and thus, the invention is intended to cover any sucharrangement. Additionally, another type of power source, other than anelectric motor, can also be used. For example, the use of a hydraulic orpneumatic motor as the drive mechanism is contemplated.

The present invention can further include a monitor for use with theorthosis 10, 80, which provides assurances the patient is properly usingthe orthosis 10, 80 during his/her exercise period. For instance, themonitor can have a position sensor, a temperature sensor, a forcesensor, a clock or timer, or a device type sensor for monitoring thepatient's implementation of a protocol. The information obtained fromthese monitoring devices may be stored for later analysis orconfirmation of proper use or may be transmitted in real-time during useof the device. The data obtained from the monitor can be analyzed by ahealthcare professional or technician and the protocol can be adjustedaccordingly.

This analysis may be conducted remotely, thereby saving the time andexpense of a home visit by a healthcare professional or technician. Anexemplary monitoring system is provided in U.S. Pat. No. 7,182,738entitled “Patient Monitoring Apparatus and Method for Orthosis and OtherDevices,” to Bonutti et al., the content of which is herein expresslyincorporated by reference in its entirety.

The components of the present invention are rigid members made of, forexample, aluminum, stainless steel, polymeric, or composite materials.The member and extensions are sufficiently rigid to transmit thenecessary forces. It should be understood that any material ofsufficient rigidity might be used, For example, some components can bemade by injection molding. Generally, for injection molding, tool anddie metal molds of the components are prepared. Hot, melted plasticmaterial is injected into the molds. The plastic is allowed to cool,forming components. The components are removed from the molds andassembled.

Furthermore, it is contemplated that the components can be made ofpolymeric or composite materials such that the device can be disposable.For example, at least some or all of the components can be made of abiodegradable material such as a biodegradable polymer. Among theimportant properties of these polymers are their tendency todepolymerize relatively easily and their ability to form environmentallybenign byproducts when degraded or depolymerized. One such biodegradablematerial is poly (hydroxyacids) (“PHA's”) such as polyactic acid (“PLA”)and polyglycolic acid (“PGA”).

Additionally, the device can be made of a nonmagnetic material. In suchinstance, the device can be used as a positioning device for use inimaging devices, such as a MRI device. It is also contemplated that thedevice can be used as a positioning device for use during surgicalprocedures, where it may be necessary to adjust and hold the position ofthe joint.

It will be appreciated by persons skilled in the art that the presentinvention is not limited to what has been particularly shown anddescribed herein above. For example, although the examples presentedidentify the wrist joint, the present invention can be used for anyjoint. In addition, unless mention was made above to the contrary, itshould be noted that all of the accompanying drawings are not to scale.A variety of modifications and variations are possible in light of theabove teachings without departing from the scope and spirit of theinvention.

1. An orthosis for stretching tissue around a joint of a patient betweenfirst and second relatively pivotable body portions, comprising: a firstarm member affixable to the first body portion; a second arm memberaffixable to the second body portion; and a third arm member interposedbetween the first and second arm members, wherein the first arm memberis slidingly connected to the third arm member and the third arm memberis operatively connected to the second arm member such that the firstand third arm members are movable from a first position to a secondposition relative to the second arm member.
 2. An orthosis as set forthin claim 1 further comprising a first cuff attached to the first armmember.
 3. An orthosis as set forth in claim 2 wherein the first cuff isfastenable about the first body portion tightly enough that the firstarm member may apply a force to the first body portion without havingthe first cuff slide along the first body portion.
 4. An orthosis as setforth in claim 2 wherein the first cuff is slidably mounted to the firstarm member.
 5. An orthosis as set forth in claim 1 further comprising asecond cuff attached to the second arm member.
 6. An orthosis as setforth in claim 5 wherein the second cuff is fastenable about the secondbody portion tightly enough that the second arm member may apply a forceto the second body portion without having the second cuff slide alongthe second body portion.
 7. An orthosis as set forth in claim 5 whereinthe second cuff is slidably mounted to the second arm member.
 8. Anorthosis as set forth in claim 1 further comprising a drive assembly onthe third arm member, the drive assembly engaging the second arm memberfor selectively moving the third arm member with respect to the secondarm member.
 9. An orthosis as set forth in claim 8 wherein the driveassembly includes a gear rotatably mounted in the third arm member. 10.An orthosis as set forth in claim 9 wherein the second arm memberincludes a plurality of teeth for engaging the gear.
 11. An orthosis asset forth in claim 10 wherein the gear is manually rotatable forselectively moving the third arm member with respect to the second armmember.
 12. An orthosis as set forth in claim 9 further comprising amotor operatively connected to the gear for selectively moving the thirdarm member with respect to the second arm member.
 13. An orthosis as setforth in claim 8 wherein the drive assembly includes a locking assembly.14. An orthosis as set forth in claim 1 wherein the second arm memberincludes a second extension member having an arcuate shape extendingtherefrom; and the third arm member includes a third extension memberhaving an arcuate shape extending therefrom, wherein the first armmember is slidingly connected to the third extension member and thethird arm member is operatively connected to the second extension memberand travels along an arcuate path defined by the second extension memberwhen the third arm member is moved from the first position to the secondposition.
 15. An orthosis as set forth in claim 14, wherein the firstarm member slides along an arcuate path defined by the third extensionmember as the third arm member is moved from the first position to thesecond position.
 16. An orthosis as set forth in claim 15, wherein thejoint defines a first plane substantially orthogonal to a longitudinalaxis of the second arm member and a second plane substantially parallelto the longitudinal axis of the second arm member.
 17. An orthosis asset forth in claim 16, wherein the second extension member extends fromthe second arm member, such that the operative connections of the first,second, and third arm members lie in the first plane.
 18. An orthosis asset forth in claim 1, further comprising a locking pin removablepositionable through the first and third arm members, such that thefirst arm member moves with the third arm member when the third armmember is moved from the first position to the second position relativeto the second arm member.
 19. An orthosis as set forth in claim 1,wherein the joint and the first and second body portions define on oneside of the joint an inner sector which decreases in angle as the jointis flexed and define on the opposite side of the joint an outer sectorwhich decreases in angle as the joint is extended, such that theoperative connections of the first, second, and third arm members arelocated in the outer sector.
 20. An orthosis for stretching tissuearound a joint of a patient between first and second relativelypivotable body portions, the joint and the first and second bodyportions defining on one side of the joint an inner sector whichdecreases in angle as the joint is flexed and defining on the oppositeside of the joint an outer sector which decreases in angle as the jointis extended, comprising: a first arm member affixable to the first bodyportion; a second arm member affixable to the second body portion andincluding a second extension member having an arcuate shape extendingtherefrom; a third arm member interposed between the first and secondarm members, wherein the first arm member is slidingly connected to thethird arm member and the third arm member is operatively connected tothe second extension member and travels along an arcuate path defined bythe second extension member when the third arm member is moved from afirst position to a second position relative to the second arm member;and a drive assembly on the third arm member, the drive assemblyengaging the second extension member for selectively moving the firstand third arm members with respect to the second arm member.
 21. Anorthosis as set forth in claim 20 wherein the third arm member includesa third extension member having an arcuate shape extending therefrom.22. An orthosis as set forth in claim 21 wherein the first arm memberslides along an arcuate path defined by the third extension member asthe third arm member is moved from the first position to the secondposition relative to the second arm member.
 23. An orthosis as set forthin claim 22 further comprising a locking pin removable positionablethrough the first and third arm members, such that the first arm membermoves with the third arm member when the third arm member is moved fromthe first position to the second position relative to the second armmember.
 24. An orthosis as set forth in claim 20 wherein the driveassembly includes a gear rotatably mounted in the third arm member. 25.An orthosis as set forth in claim 24 wherein the second arm memberincludes a plurality of teeth for engaging the gear.
 26. An orthosis asset forth in claim 24 wherein the gear is manually rotatable forselectively moving the third arm member with respect to the second armmember.
 27. An orthosis as set forth in claim 24 further comprising amotor operatively connected to the gear for selectively moving the thirdarm member with respect to the second arm member.
 28. An orthosis as setforth in claim 20 wherein the drive assembly includes a lockingassembly.